Testing Interfaces; Sending Bert Patterns - Juniper PHYSICAL LAYER - CONFIGURATION GUIDE V11.1.X Configuration Manual

Testing Interfaces

Testing interfaces allows you to troubleshoot problems and to check the quality of
links at various layers in the interface stack. The router supports the following test
options:

Sending BERT Patterns

The router can send BERT patterns from different layers in the interface stack on
frame-based T3 interfaces.
For a list of the modules that support bit error rate tests, see ERX Module Guide,
Appendix A, Module Protocol Support.
To send BERT patterns:
1.
2.
bert
Transmission of BERT patterns to remote devices
Local loopback—Loops the data back toward the router; on supported line
modules, also sends an alarm indication signal (AIS) out toward the network
Network loopback Loops the data toward the network before the data reaches
the frame
Payload loopback Loops the data toward the network after the framer processes
the data
Remote loopback Provides the ability to:
Request that remote devices enter into loopback
Be placed in loopback by remote devices
Select a controller.
host1(config)#controller t3 3/2
Configure a specific layer in the interface to generate BERT patterns.
host1(config-controll)#bert pattern 2^11 interval 10
For information about BERT patterns, see "References" on page 50.
Use to enable bit error rate tests using the specified pattern on a T3 interface.
Unlike other configuration commands, bert is not stored in NVRAM.
Specify one of the following test patterns:
0s Repetitive test pattern of all zeros, 00000...
1s Repetitive test pattern of all ones, 11111...
2^9 Pseudorandom test pattern, 511 bits in length
Chapter 2: Configuring T3 and E3 Interfaces
Testing Interfaces
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